Difference between electrostriction kinetics, and mechanical response of segmented polyurethane-based EAP

J Jomaa (1) , L. Seveyrat (2) , V Perrin (2) , L Lebrun (2) , Karine Masenelli-Varlot (3) , Gildas Diguet (4) , Cavaillé J.-Y. (4, 3)

1 UCL - University College of London [London]
2 LGEF - Laboratoire de Génie Electrique et Ferroélectricité
3 MATEIS - Matériaux, ingénierie et science [Villeurbanne]
4 ELyTMaX

Among the key parameters, which must be taken into account for the choice of actuators used as electrical to mechanical energy converters, the response to a step function and/or the frequency dependence of this response is extremely important. For polymeric actuators and more generally for electroactive polymers, three mechanisms can be at the origin of energy losses, namely dielectric relaxations, viscoelastic relaxations and possible electrical conductivity. In a previous paper, we studied the electrical behavior of segmented polyurethanes with different weight fractions of hard (MDI-BDO) and soft (PTMO) segments. They were shown to exhibit three main mechanisms, namely, from the fastest to the slowest, a secondary or β-relaxation, the main or α-relaxation associated with the glass–rubber transition of the soft phase, and finally, their electrical conductivity. In the present work, we present the general viscoelastic response (as measured through mechanical spectrometry) of the same polyurethanes and their respective time dependent electrostriction responses, and compare it with the relaxation characteristic times of electrical and mechanical spectroscopy data.

Mots clés: Polymers; Polyurethanes; Viscoelasticity; Electrical behaviors; Electrical conductivity; Electro-active polymers; Frequency dependence; Mechanical spectroscopy; Segmented polyurethanes; Viscoelastic relaxation; Viscoelastic response; Mechanical actuators; Electrostriction; Energy dissipation; Glass transition; Actuators; Anelastic relaxation; Conducting polymers; Electric conductivity; Mechanisms; Organic polymers

Domaines: Electromagnétisme; Mécanique des matériaux [physics.class-ph]

J Jomaa, L. Seveyrat, V Perrin, L Lebrun, Karine Masenelli-Varlot, et al.. Difference between electrostriction kinetics, and mechanical response of segmented polyurethane-based EAP. Smart Materials and Structures, 2017, 26 (3), ⟨10.1088/1361-665X/aa5c4b⟩. ⟨hal-01831636⟩